Steve's 79 CM400A

Yeah, that was a good find over at David Silver Spares. Kind of the only option we got. I checked with Daniel Stern lighting and there is no option for that headlight size unless you switch to a 7" bucket.
 
Just a quick one, and probably minor, but I went out tonight to start the bike, and the halogen headlight is barely lighting up...maybe about as bright as the turn signals are. I can't say if it's a new issue, because I only ride in daylight. I took it for a ride around the block anyway, thinking maybe something would make it brighten up, but nope. It's not shining bright enough to see anything in front at night...I was riding by turn signal glow.
 
No, I switched from high beam to low beam, back and forth, and nothing changes. I'm getting a short video ready to post here in a bit.
 
that would indicate to me its probably the fuse. have you tried wiggling the second fuse? the top one is the main, second is headlight and third is turn signals/tail.
 
thats strange. maybe the bulb is just cheap and weak? if not, only thing i can guess is a wiring issue that is causing excess draw so the light cant work its best.
 
I'm not too overly concerned about it since I don't ride at night, and it does light up enough to be legal during the day, but I'll still check the fuses tomorrow.
 
Maraakate said:
that would indicate to me its probably the fuse. have you tried wiggling the second fuse? the top one is the main, second is headlight and third is turn signals/tail.
Click to expand...
In-between the annoying things that pop up to keep me from checking things out, I did get to the fuses, and the middle fuse looked like it exploded inside the glass. It was so bad one end actually fell off when I took it out. Everything I can find says it's supposed to be a 7A fuse for the headlight, but that's for a stock headlight - does an H4 55/60W halogen headlight bulb need a bigger fuse, or should I put another 7A in there?
 
You don't need a bigger fuse. 7A is plenty. There should be a spare. I was pretty sure I replaced that fuse, but maybe I was mistaken. Replace it with another 7A (if you must use an 8A or 10A due to availability this is OK, but no higher). If it blows immediately upon replacing, then there is an obvious short somewhere. If it takes some time, then there's probably something rubbing by vibration or internal resistance in a wire.
 
I tried both spare fuses and neither of them got the headlight to turn on. I'll get a new 7A fuse and see what happens. Inside the headlight housing those odd "parking lights" do come on.
 
The parking light in the headlight is actually part of the tail light circuit so that is not unusual.

Did both spare fuses pop?
 
Try rotating them in the holder. If it still does not come on, then there's a very real possibility the bulb blew or there is a wiring problem. If there is a wiring problem, I can't really guide you too much online I'd have to physically see it.
 
I put a new H4 55/60W bulb in, thinking that was the issue, and thought maybe I screwed that up somehow, but I can't think of how I could screw up something that's plug and play. The fuse "holders" that hold the fuse ends looked loose, so I did give them a gentle squeeze so they hold the fuse ends tighter, but that didn't work.

I'll get a new 7A fuse and see what happens. Thanks, Frank!
 
The headlight issue ended up just being a wire in the headlight that came undone. I pushed it back in place and the headlight works again.

That's the good news - the bad news is now there's another issue. I just took the bike for a short ride, no issues at all with it running or anything...I parked it in my usual spot, shifted it down to neutral like always, and turned it off, and turned off the petcock, as always. Then I thought I wanted to check the headlight and be sure the high beams/low beams were working, so I put the key back in, turned it to "on", and nothing. No indicator lights, no starting, not even cranking...nothing at all. What the?
 
Wiggle the top fuse and see. You disturbed them earlier. Also, if you put the wrong fuse in the top may have blown. Supposed to be a 10A fuse. If it was lower that is a problem. Just FYI, in an emergency you CAN kickstart it and ride it home.
 
Maraakate said:
Wiggle the top fuse and see. You disturbed them earlier. Also, if you put the wrong fuse in the top may have blown. Supposed to be a 10A fuse. If it was lower that is a problem. Just FYI, in an emergency you CAN kickstart it and ride it home.
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The top fuse is good, but for the life of me I can't read what amp it is. Also, the fuse box cover says the main is 15 amp. Should I buy a 10 amp and put that in?
 
Popped a new 15 amp fuse in it and it started right up, so thanks again!

And that, my friends, is why Frank is The Man (y)
 
I had an interesting ride today, and a learning experience, and I'm glad to have learned something new with this bike that's been so enjoyable.

It was 23 degrees outside - that will probably tell you where this is going. The bike started fine, ran like a champ, as always. After about 10 minutes of in-town speeds of 25-35 MPH, the road turned into a 55 MPH zone and I got the bike to 55 MPH, with no issues at all, cruising right along. But after about a minute at 55 MPH, power just started to fade. No noises, no clunking, nothing...just power slowly fading away. I got off the throttle and tried nursing it back to speed, but it just didn't want to go, so I pulled over and stopped (kept it running)...I sat there for maybe 20 seconds, turned it around and got back on the road to head home, and it got right up to 55 MPH with no problem, like nothing had happened. I was back to in-town speeds about a minute later, and the whole ride home was just as smooth as every time I ride the bike.

Since the bike gave no signs of trouble, like noises or anything else, my only thought was that the cold air must have been too much for the bike at 55 MPH. In town, it sailed right along, purring like a kitten like it always does. I came home and read about cold temps and carbureted engines, and I won't go back to high speed roads again through the winter when the temps dip that low...I'll keep the bike at or below around 40 MPH, where it rode perfectly fine today. In fact, yesterday it was 38 degrees, and I was on the same road at the same speeds and everything ran like clockwork - and now I know.

On a sidenote, my sister is getting tired of hearing about how much I love this bike...hahaha! Actually, she's happy for me.
 
23 degrees, yikes thats a little below my weather minimums. I picked up a Neck Gaiter and some gortex gloves for cheap, I'm planning on riding in some 40 degree weather, but not 20's Glad you are enjoying yourself though.
 
In the occasional saga of me doing dumb things because I'm not mechanical like you guys, when I took the battery out of the bike (first time I've ever done that) I didn't know about the little square nuts that sit inside the battery terminals. Naturally, when the battery came out, so did those nuts, and now they're somewhere inside a two-foot snowbank where the bike is parked.

No biggie - I ordered a little box of M6 nuts and square bolts. But what I also did was ordered some 3/4-inch clear tubing, I cut about an inch off and cut that in half the long way, and stuffed those pieces of tubing into the terminals behind the square nuts so they won't go flying the next time I mess with the battery. The tubing fit nice and snug inside the terminals, they have a tight hold on the square nuts, and all is well now.

Ahhhhhhhhhhh...first-world newbie problems (hahaha)! :p


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Years ago, I acquired the habit of partially screwing bolts back into where they came from while servicing something.
It's saved me countless times... ..e.g., engine side cover bolt lengths vary in length (as do the holes in the crankcase into which they install)
 
Boosted said:
Years ago, I acquired the habit of partially screwing bolts back into where they came from while servicing something.
It's saved me countless times... ..e.g., engine side cover bolt lengths vary in length (as do the holes in the crankcase into which they install)
Click to expand...
Good practice. I'll do that or lay everything out on a workbench or table. You always think, 'I'll remember that,' until you don't when you come back 3 weeks later.
 
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